Inkjet printers are well known in the art. Ink compositions that are curable by application of radiation, in particular UV radiation are also well known in the art. Such inkjet printers employing an UV-curable ink are typically used in professional printing (i.e. not for home or office use). In particular, the known UV-curable inkjet printer assemblies are common in the graphical arts printing industry.
In the professional printing industry, it is known and common to apply separate air ventilation systems to vent the space in which the printer assemblies are positioned.
During printing, curing of the ink results in emissions that have a typical, usually unpleasant smell. Moreover, depending on the particular ink composition and the emitted concentrations, the emissions may even be unhealthy. The ventilation systems remove the polluted air to an extent that the polluted air may not be unhealthy, but the smell remains.
JP2007098665 discloses an inkjet printer configured to eject UV-curable inkjet ink and cure the ink by application of UV radiation. In order to prevent emissions and odor, an adsorption means is provided inside a tightly closed print space. Thus, any emissions are prevented from entering the environment.
Further, UV radiation may be harmful to the human eye and skin. So, the printer assemblies known from the prior art have specific measures and features prevent that UV radiation is irradiated in another direction than towards the droplets of ink on a printed medium. However, usual radiation sources generate a relatively large amount of heat. Any measures and features for shielding of the UV radiation result in isolation and additional measures and features may be required to prevent overheating of the UV-radiation source. Moreover, in JP2007098665, the closed print space prevents cooling by convection. Additionally, any additional measures and features for protection against UV radiation limit the view on an image printed on the recording medium.
Despite all the above described technical limitations, the professional operator in the graphical arts is used to and prefers to be able to see the image print result as it is printed. Any artifacts and defects in the printed result should be identified as soon as possible such to be able to minimize unusable and therefore unsellable prints and such to enable to correct any incorrect print settings as soon as possible.
In an inkjet printer employing a gelling UV-curable ink, it may be advantageous to apply the UV radiation over a relatively large area having a predetermined radiation intensity profile. The ink is then suitably cured, but emissions may increase. Further, to prevent UV radiation becoming harmful, in such a printer, additional measures may be applied further limiting the view on the printed image. Even further, to prevent thermal de-gelling of the applied ink droplets, a temperature within the printer space should be kept suitably low.
It is desirable to have a printer assembly that is simple and cost effective, while addressing the above indicated technical limitations and operator desires.